European Journal of Organic Chemistry

Cover image for Vol. 2014 Issue 22

Early View (Online Version of Record published before inclusion in an issue)

Editor: Haymo Ross, Deputy Editor: Susan Wilkinson

Impact Factor: 3.344

ISI Journal Citation Reports © Ranking: 2012: 14/57 (Chemistry Organic)

Online ISSN: 1099-0690

Associated Title(s): Advanced Synthesis & Catalysis, Asian Journal of Organic Chemistry

VIEW

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  1. Full Papers

    1. Regiospecific Nitration

      Regiospecific Synthesis of Substituted 2-Nitrobenzaldehydes from Benzaldehydes through Palladium-Catalyzed Chelation-Assisted C–H Nitration

      Wei Zhang, Degui Wu, Jian Zhang and Yunkui Liu

      Article first published online: 25 JUL 2014 | DOI: 10.1002/ejoc.201402451

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      An efficient and general method for the regiospecific synthesis of substituted 2-nitrobenzaldehydes from related benzaldehydes has been developed. The approach involves palladium-catalyzed chelation-assisted C–H nitration as the key step, and enables regiospecific nitration of C–H bonds free from the effect of orientation rules.

    2. Bioactive Natural Products

      Eudesmane-Type Sesquiterpenes from Curcuma phaeocaulis and Their Inhibitory Activities on Nitric Oxide Production in RAW 264.7 Cells

      Yue Liu, Jianghao Ma, Ying Wang, Paul Owusu Donkor, Qin Li, Suyu Gao, Yaguang Hou, Yang Xu, Jianing Cui, Liqin Ding, Feng Zhao, Ning Kang, Lixia Chen and Feng Qiu

      Article first published online: 25 JUL 2014 | DOI: 10.1002/ejoc.201402465

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      Eight new sesquiterpenes (phaeusmanes A–H), together with eighteen known analogues, were isolated from the rhizomes of Curcuma phaeocaulis. Their complete structures were elucidated by NMR, MS, and CD spectroscopy. The NO inhibitory effects of the isolates are presented. A possible biogenetic pathway for N-containing eudesmane-type sesquiterpene 8 is postulated.

    3. Nitrogen Heterocycles

      Concise Synthesis of Substituted Quinolizin-4-ones by Ring-Closing Metathesis

      Thomas A. Alanine, Warren R. J. D. Galloway, Thomas M. McGuire and David R. Spring

      Article first published online: 25 JUL 2014 | DOI: 10.1002/ejoc.201402648

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      4H-Quinolizin-4-ones are of significant pharmaceutical interest, yet they are infrequently explored for drug discovery because of difficulties with synthetic accessibility. A new strategy is reported for the synthesis of this rare and biologically interesting class of compounds.

  2. Short Communications

    1. Sequential Reactions

      One-Pot Sequential Schmidt and Ritter Reactions for the Synthesis of N-tert-Butyl Amides

      Nabajyoti Hazarika and Gakul Baishya

      Article first published online: 25 JUL 2014 | DOI: 10.1002/ejoc.201402662

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      A mixture of NaN3/HBF4·OEt2 in AcOH reacts efficiently with aromatic and conjugated (α,β-unsaturated) aldehydes to produce nitrile derivatives, which in situ undergo a Ritter reaction with tert-butyl acetate to afford the corresponding N-tert-butyl amides. The method needs no column chromatography purification, has a wide substrate scope, and uses readily available reagents.

  3. Full Papers

    1. Glycosylation

      Gold(III) Chloride and Phenylacetylene: A Catalyst System for the Ferrier Rearrangement, and O-Glycosylation of 1-O-Acetyl Sugars as Glycosyl Donors

      Rashmi Roy, Parasuraman Rajasekaran, Asadulla Mallick and Yashwant D. Vankar

      Article first published online: 24 JUL 2014 | DOI: 10.1002/ejoc.201402606

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      The Ferrier rearrangement of glycals, and the glycosylation of 1-O-acetyl sugars using an AuCl3/phenylacetylene catalyst system are described. Relay catalysis was observed when phenylacetylene was used in combination with AuCl3. The efficient production of glycosides was achieved in shortened reaction times.

    2. Regiospecific Synthesis

      Regiospecific Synthesis of 7-Hydroxyindoles from Pyrroles by Anionic Benzannulation

      Bidyut Kumar Dinda, Shyam Basak and Dipakranjan Mal

      Article first published online: 24 JUL 2014 | DOI: 10.1002/ejoc.201402486

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      7-Hydroxyindoles have been regioselectively synthesized in good yields by implementation of anionic [4+2] cycloaddition reactions on 2,3-disusbtituted pyrroles. The methodology has also been applied to furan analogues for the synthesis of 7-hydroxybenzofurans.

    3. Asymmetric Catalysis

      Enantioselective Hydrosilylation of Ketones Catalyzed by a Readily Accessible N-Heterocyclic Carbene–Ir Complex at Room Temperature

      Kanako Shinohara, Shun Kawabata, Hanako Nakamura, Yoshiki Manabe and Satoshi Sakaguchi

      Article first published online: 23 JUL 2014 | DOI: 10.1002/ejoc.201402279

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      Stable monodentate NHC–Ir complexes containing hydroxy-amide groups on the side-arm could be synthesized with ease from naturally occurring amino acids such as leucine. Using these complexes, asymmetric hydrosilylation of aryl ketones with diethoxymethylsilane under very mild and flexible conditions readily afforded optically active alcohols with good enantioselectivities (73–96 % ee).

    4. Molecular Synthons

      2,5-Diamide-Substituted Five-Membered Heterocycles: Challenging Molecular Synthons

      Chiara Fabbro, Simone Armani, Laure-Elie Carloni, Federica De Leo, Johan Wouters and Davide Bonifazi

      Article first published online: 23 JUL 2014 | DOI: 10.1002/ejoc.201402654

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      2,5-Diamide-substituted five-membered heterocycles could easily be prepared from the corresponding biscarboxylic acid precursors by means of a Curtius-type rearrangement.

    5. Spiro Compounds

      Highly Enantioselective Construction of Spirocyclopentaneoxindoles Containing Four Consecutive Stereocenters through an Organocatalytic Iminium–Enamine Cascade Reaction

      Liang-Zhong Ding, Tong-Sheng Zhong, Hao Wu and Yong-Mei Wang

      Article first published online: 23 JUL 2014 | DOI: 10.1002/ejoc.201402687

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      Biologically important and synthetically challenging spirocyclopentaneoxindole derivatives containing four consecutive stereocenters, including one spiro quaternary center, are constructed with excellent enantio- and diastereomeric purities by an organocatalytic iminium–enamine cascade sequence between 3-substituted bifunctional oxindoles and α,β-unsaturated aldehydes under mild conditions.

  4. Short Communications

    1. Heterocycles

      Synthesis of 1,2,4-Thiadiazoles by Oxidative Dimerization of Carbothioamides by Using Oxone

      Akira Yoshimura, Anthony D. Todora, Brent J. Kastern, Steven R. Koski and Viktor V. Zhdankin

      Article first published online: 23 JUL 2014 | DOI: 10.1002/ejoc.201402756

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      1,2,4-Thiadiazoles are efficiently synthesized in good yields through the oxidative dimerization of carbothioamides by using Oxone as a readily available, inexpensive, and environmentally safe oxidant.

    2. Click Chemistry

      Convenient Access to Carbohydrate–­BODIPY Hybrids by Two Complementary Methods Involving One-Pot Assembly of “Clickable” BODIPY Dyes

      Mayra R. Martinez-Gonzalez, Arlette Urías-Benavides, Enrique Alvarado-Martínez, J. Cristobal Lopez, Ana M. Gómez, Mayca del Rio, Inmaculada Garcia, Angel Costela, Jorge Bañuelos, Teresa Arbeloa, Iñigo Lopez Arbeloa and Eduardo Peña-Cabrera

      Article first published online: 23 JUL 2014 | DOI: 10.1002/ejoc.201402767

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      Two complementary one-pot, three-component methodologies are described that allow the click copper(I)-catalyzed azide–alkyne cycloaddition of azido– or alkyne–carbohydrates with alkyne– or azide–BODIPY derivatives, respectively, and pave the way to water-soluble carbohydrate–difluoroboron-dipyrromethene hybrids.

    3. Natural Product Synthesis

      Application and Scope of Schreiber's Gold(I)-Catalyzed α-Pyrone Synthesis to Ring A Aromatic Podolactones

      Eduardo Sánchez-Larios, Robert D. Giacometti and Stephen Hanessian

      Article first published online: 22 JUL 2014 | DOI: 10.1002/ejoc.201402803

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      Schreiber's gold(I)-catalyzed synthesis of α-pyrones is adapted to the total synthesis of a ring A aromatic analog of urbalactone. The scope of the acetylenic ester partner in the formation of α-pyrones is also studied. Notably, several α-pyrone intermediates from this work exhibit in vitro antiproliferative activity against the A2780 ovarian cancer cell line.

  5. Full Papers

    1. Coupling Reactions

      Copper(I)-Catalyzed Decarboxylative Coupling of Propiolic Acids with Secondary Amines and Aldehydes

      Denis S. Ermolat'ev, Huangdi Feng, Gonghua Song and Erik V. Van der Eycken

      Article first published online: 22 JUL 2014 | DOI: 10.1002/ejoc.201402338

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      A number of tertiary propargylamines was prepared by a copper(I)-catalyzed decarboxylative A3-coupling reaction of an alkynylcarboxylic acid with a secondary amine and an aldehyde. The procedure is also effective for 3-alkylpropiolic acids and for terminal propiolic acid.

    2. Heterocycles

      Synthesis, Stability, and Photoreactivity of Diazirinyl-Substituted N-Heterocycles Based on Indole, Benzimidazole, and Imidazole

      Björn Raimer, Thomas Wartmann, Peter G. Jones and Thomas Lindel

      Article first published online: 22 JUL 2014 | DOI: 10.1002/ejoc.201402354

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      Benzimidazole leads among N-heterocycles that carry a 2-diazirinyl unit with regard to accessibility and thermal stability. Care is required with the labile imidazole analog; and N-methylated 2-diazirinylindole was also not stable. The investigated 2-diazirines are singlet carbene sources, as confirmed by DFT calculations. Irradiation in the presence of phenol forms the O-, p-, and o-products.

    3. Chiral Pool Synthesis

      A Concise Synthesis of (2R,3R)- and (2R,3S)-3-Hydroxypipecolic Acids, and Total Synthesis of (–)-Deoxoprosopinine and (+)-2-epi-Deoxoprosopinine from D-Glycals

      Asadulla Mallick, Nitee Kumari, Rashmi Roy, Ashokkumar Palanivel and Yashwant D. Vankar

      Article first published online: 22 JUL 2014 | DOI: 10.1002/ejoc.201402603

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      New syntheses of (2R,3R)- and (2R,3S)-3-hydroxypipecolic acids, and total syntheses of (–)-deoxoprosopinine and (+)-2-epi-deoxoprosopinine are reported. The syntheses started from D-glycals, and Ferrier rearrangement, intramolecular cyclization, and Grignard reactions were key steps.

  6. Short Communications

    1. Electrosynthesis

      Electrochemical Deoxygenation of Aromatic Amides and Sulfoxides

      Carolin Edinger and Siegfried R. Waldvogel

      Article first published online: 22 JUL 2014 | DOI: 10.1002/ejoc.201402714

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      The electrochemical deoxygenation of a broad range of aromatic carboxamides is achieved under mild conditions. Furthermore, sulfides can be readily prepared by subjecting the corresponding sulfoxides to the elaborated electroreductive strategy.

  7. Full Papers

    1. Spiro Compounds

      Synthesis of the Spiroketal Fragment of (–)-Ushikulide A

      Jhillu S. Yadav, N. Mallikarjuna Reddy, Md. Ataur Rahman and Attaluri R. Prasad

      Article first published online: 21 JUL 2014 | DOI: 10.1002/ejoc.201402196

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      The stereoselective synthesis of the spiroketal fragment of (–)-Ushikulide A is described. The key tetrahydropyran moiety was synthesized by using segment-coupled Prins cyclization of an α-acetoxy ether. Both iodohydrin derivatives were obtained from a common THP ring compound by reductive ring cleavage under Boord reaction conditions.

    2. Heteroannulation

      Iron-Promoted Domino Annulation of α-Enolic Dithioesters with Ninhydrin under Solvent-Free Conditions: Chemoselective Direct Access to Indeno[1,2-b]thiophenes

      Suvajit Koley, Sushobhan Chowdhury, Tanmoy Chanda, B. Janaki Ramulu, Ganesh Chandra Nandi and Maya Shankar Singh

      Article first published online: 21 JUL 2014 | DOI: 10.1002/ejoc.201402276

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      The chemoselective synthesis of indeno[1,2-b]thiophenes was developed through the annulation of α-enolic dithioesters with ninhydrin under solvent-free conditions. This domino reaction sequence is highlighted by the use of inexpensive FeCl3·6H2O, its operational simplicity, a short reaction time, its functional-group tolerance, and the concomitant formation of two bonds and one thiophene ring.

    3. Domino Process

      Dual Catalysis in Domino N-Benzylation/Intramolecular C–H Arylation: Regio- and Chemoselective Synthesis of Annelated Nitrogen Heterocycles

      Joydev K. Laha, Neetu Dayal, Swati Singh and Rohan Bhimpuria

      Article first published online: 21 JUL 2014 | DOI: 10.1002/ejoc.201402395

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      A regio- and chemoselective synthesis of fused nitrogen heterocycles is described that proceeds through a domino N-benzylation/C–H arylation reaction sequence. The dual catalysis of this domino process is supported by a mechanistic study.

    4. Nonproteinogenic Amino Acids

      Biocatalytic Synthesis of Enantiopure β-Methoxy-β-arylalanine Derivatives

      Shiming Fan, Shouxin Liu, Hubo Zhang, Ying Liu, Yihuang Yang and Longyi Jin

      Article first published online: 21 JUL 2014 | DOI: 10.1002/ejoc.201402470

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      Chiral β-hydroxy-β-arylalanine and β-methoxy-β-arylalanine derivatives were prepared stereoselectively from ethyl 3-oxo-3-arylpropanoates through oximation, hydrogenation, N-acetylation, methylation, and enzyme-catalyzed hydrolysis.

    5. Multicomponent Reactions

      A Three-Component Reaction for the Synthesis of Diverse, Densely Substituted 2′,3′-Dihydrospiro[indoline-3,6′-[1,3]oxazine]s

      Jing Zhang, Hong Gao, Jing Sun and Chao-Guo Yan

      Article first published online: 21 JUL 2014 | DOI: 10.1002/ejoc.201402500

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      Three-component reactions of α,β-unsaturated N-arylaldimines, dialkyl acetylenedicarboxylate, and N-alkylisatins afforded 3′-aryl-2′-styryl-2′,3′-dihydrospiro[indoline-3,6′-[1,3]oxazine]s in good yields.

    6. Spiroaminals

      Spiroaminals – Crystal Structure and Computational Investigation of Conformational Preferences and Tautomerization Reactions

      Claudia Loerbroks, Birte Böker, Jens Cordes, Anthony G. M. Barrett and Walter Thiel

      Article first published online: 21 JUL 2014 | DOI: 10.1002/ejoc.201402576

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      A joint experimental and computational study reveals the driving forces in the equilibria of spiroaminals. Although thermodynamic and electronic factors such as the anomeric effect lower the energy of the spiroaminal form, steric repulsion in combination with kinetic barriers favor the amine/imine structure. DFT calculations elucidate the mechanism of tautomerization.

    7. Stereoselective Synthesis

      Stereoselective Synthesis of Lignans of Three Structural Types from a Common Intermediate, Enantioselective Synthesis of (+)-Yangambin

      Majid Khalil Syed, Cian Murray and Mike Casey

      Article first published online: 21 JUL 2014 | DOI: 10.1002/ejoc.201402584

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      Construction of a bis(phenylpropanoid) backbone through a one-pot conjugate addition/aldol reaction. Reduction and acid-catalysed cyclisation of the aldol intermediate gave (+)-yangambin in good yield with 2,5-diaryltetrahydrofuran lignans as minor products, whereas the acid-catalysed cyclisation of the aldol intermediate resulted in a derivative of the lignan lirionol.

    8. Ring-Rearrangement Metathesis

      Diversity-Oriented Approach to Carbocycles and Heterocycles through Ring-Rearrangement Metathesis, Fischer Indole Cyclization, and Diels–Alder Reaction as Key Steps

      Sambasivarao Kotha and Ongolu Ravikumar

      Article first published online: 18 JUL 2014 | DOI: 10.1002/ejoc.201402273

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      Dicyclopentadiene derivatives were subjected to ring-rearrangement metathesis to deliver a range of fused polycycle frameworks containing carbocycles, oxacycles, and azacycles. Here, Fischer indole cyclization and the Diels–Alder reaction are employed as key steps.

    9. Cucurbitane Triterpenes

      Roseic Acid and Roseolactones A and B, Furan-Cucurbitane Triterpenes from Russula aurora and R. minutula (Basidiomycota)

      Marco Clericuzio, Giovanni Vidari, Claudio Cassino, Laura Legnani and Lucio Toma

      Article first published online: 18 JUL 2014 | DOI: 10.1002/ejoc.201402208

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      The fruiting bodies of the gilled fungi Russula aurora and R. minutula give a coral pink colour with sulfo-vanillin (SV). We found that they synthesize a few triterpenes, belonging to the seco-cucurbitane series, a rare skeleton type. These compounds show the above reaction with SV on TLC. Assignment of the configurations of 2 and 3 required a thorough ab initio theoretical investigation.

  8. Microreviews

    1. Halonitro Compounds

      Recent Developments in the Chemistry of gem-Halonitro Compounds

      Raquel G. Soengas, Rita C. Acúrcio and Artur M. S. Silva

      Article first published online: 17 JUL 2014 | DOI: 10.1002/ejoc.201402043

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      gem-Halonitro compounds have important practical applications in biology and industry and are also valuable synthetic intermediates of growing chemical interest. In the past few years these derivatives have come to be recognized as powerful synthetic tools. In this review we discuss recent developments in the chemistry of gem-halonitro compounds.

  9. Full Papers

    1. Nitrogen and Oxygen Heterocycles

      N-Acyl-N-tosylhydrazine as a Synthon To Construct Tetrasubstituted Carbon Centers Possessing a Nitrogen Group

      Kosuke Namba, Yoshihiro Shobo, Kazuki Fujimoto, Isamu Shoji, Masahiro Yoshida and Keiji Tanino

      Article first published online: 17 JUL 2014 | DOI: 10.1002/ejoc.201402650

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      New halohydrazidation and hydrazidopalladation reactions were developed that use the synthon N-acyl-N-tosylhydrazine. The intramolecular bromohydrazidation reactions of β,γ-unsaturated N-acyl-N-tosylhydrazines gave pyrazolidinone ring systems. The intramolecular hydrazidopalladation reactions of γ,δ-unsaturated N-acyl-N-tosylhydrazine afforded hydropyridazine ring systems.

    2. Total Synthesis

      Unsymmetrical vic-Tricarbonyl Compounds for the Total Syntheses of Cladoniamide G and Cladoniamide F

      Julia Schütte, Frank Kilgenstein, Michel Fischer and Ulrich Koert

      Article first published online: 17 JUL 2014 | DOI: 10.1002/ejoc.201402531

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      The enantioselective addition of indoles to mesoxalic ester amides has been investigated and the feasibility of these vic-tricarbonyl compounds as building blocks in natural product synthesis is shown in the syntheses of cladoniamide G and F. The synthesis involves arylation of a mesoxalic ester amide, a Suzuki cross-coupling to a 2,2′-biindole, and an intramolecular lactam formation as key steps.

    3. Aromaticity

      Aromaticity and Magnetic Properties of 1- and 2-Indenones and Their Aza Derivatives

      Jordi Poater, Miquel Solà, Ibon Alkorta and José Elguero

      Article first published online: 17 JUL 2014 | DOI: 10.1002/ejoc.201402509

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      1-Indenones are more stable than 2-indenones because they are more aromatic and have a more stabilizing π-component of the orbital interaction term. Tetrafluorination affects the 19F–19F spin-spin coupling constants of the 2-one series, but has no effect on the aromaticity.

    4. Fluorine Migration

      Fluoro-Ene Reaction Versus [2+2] Cycloaddition in the Thermal C2–C6 Cyclization of Enyne-Allenes: An Experimental and Theoretical Investigation

      M. Emin Cinar, Chandrasekhar Vavilala, Ralph Jaquet, Jan W. Bats and Michael Schmittel

      Article first published online: 17 JUL 2014 | DOI: 10.1002/ejoc.201402438

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      [1,5]-Fluorine migration has been attempted by using σ,π-diradical intermediate generated by the thermal C2–C6 (Schmittel) cyclization of enyne-allenes that have a fluorine atom proximate to the allene terminus. DFT calculations, including potential energy surfaces, shed light on this intriguing fluorine shift.

    5. Chiral Ionic Liquids

      Chiral Room Temperature Ionic Liquids as Enantioselective Promoters for the Asymmetric Aldol Reaction

      Laura González, Jorge Escorihuela, Belén Altava, M. Isabel Burguete and Santiago V. Luis

      Article first published online: 17 JUL 2014 | DOI: 10.1002/ejoc.201402436

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      Chiral ionic liquids derived from natural amino acids are shown to be efficient solvents or additives for direct asymmetric aldol reactions. A match/mismatch effect between the configuration of the chiral ionic liquid and that of proline has been observed, with a higher enantioselectivity obtained for the (S)-proline/CIL 2 complex.

    6. 1,4-Dihydropyridines

      Synthesis of 1,4-Dihydropyridines and Their Fluorescence Properties

      Shunsuke Sueki, Ryo Takei, Yuto Zaitsu, Junya Abe, Akane Fukuda, Keisuke Seto, Yukio Furukawa and Isao Shimizu

      Article first published online: 17 JUL 2014 | DOI: 10.1002/ejoc.201402426

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      The multicomponent coupling reactions of amine hydrochlorides, aldehydes, and acetals with various electron-withdrawing groups afford 2,6-unsubstituted 1,4-dihydropyridines (1,4-DHPs) in good yields and with high functional group tolerance. The fluorescence properties of the synthesized 1,4-DHPs have been evaluated.

    7. Hydrothiolation

      Efficient Synthesis of Isothiochromene Derivatives by Pd-Catalyzed Hydrothiolation Reaction

      Jie Feng, Meifang Lv, Guoping Lu and Chun Cai

      Article first published online: 15 JUL 2014 | DOI: 10.1002/ejoc.201402611

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      Isothiochromene could be efficiently synthesized by palladium-catalyzed intramolecular hydrothiolation. This protocol is free of foul-smelling thiols and enjoys excellent yields and excellent 6-endo-dig selectivities.

    8. Atropisomerism

      Synthesis and Characterisation of 1,7-Di- and Inherently Chiral 1,12-Di- and 1,6,7,12-Tetraarylperylenetetracarbox-3,4:9,10-diimides

      Bernard Pagoaga, Louis Giraudet and Norbert Hoffmann

      Article first published online: 15 JUL 2014 | DOI: 10.1002/ejoc.201402625

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      Perylene bisimide derivatives possessing aryl substituents in the bay positions have been synthesised and characterised, including the inherently chiral C2 and D2 symmetric derivatives. Pure enantiomers have been prepared.

    9. Circular Dichroism

      Determination of the Stereostructure of Pyrimidine Nucleoside Derivatives with a Combination of Various Chiroptical Methods

      Marcin Górecki, Aleksandra Karczmarska-Wódzka, Renata Kołodziejska, Marcin Dramiński and Jadwiga Frelek

      Article first published online: 15 JUL 2014 | DOI: 10.1002/ejoc.201402190

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      The absolute configuration of pyrimidine nucleoside derivatives obtained by enantioselective reduction was determined using a combination of electronic circular dichroism (ECD) and vibrational circular dichroism (VCD) spectroscopy in tandem with quantum chemical calculations.

    10. Donor–Acceptor Systems

      Synthesis, Electrochemistry, Crystal Structures, and Optical Properties of Quinoline Derivatives with a 2,2′-Bithiophene Motif

      Aneta Slodek, Michal Filapek, Grazyna Szafraniec, Iwona Grudzka, Wojciech Andrzej Pisarski, Jan Grzegorz Malecki, Lidia Zur, Malgorzata Grela, Witold Danikiewicz and Stanislaw Krompiec

      Article first published online: 15 JUL 2014 | DOI: 10.1002/ejoc.201402241

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      Bithiophene-quinoline acceptor-donor materials have been prepared and their absorption and luminescence have been investigated. The quinolines are blue–green and orange–red emitters. The electrochemical, optical, and theoretical (DFT) characterization show the strong influence of the character of the substituent on the quinoline ring on their electrochemical and spectroscopic properties.

    11. Natural Products

      Synthesis and Cytotoxic Activity of a Small Naphthoquinone Library: First Synthesis of Juglonbutin

      Elke Brötz, Jennifer Herrmann, Jutta Wiese, Heidi Zinecker, Armin Maier, Gerhardt Kelter, Johannes F. Imhoff, Rolf Müller and Thomas Paululat

      Article first published online: 15 JUL 2014 | DOI: 10.1002/ejoc.201402272

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      A synthetic protocol has been designed to synthesize a small naphthoquinone library based around the natural products grecoketidone, hydroxylapachol, and juglonbutin. Biological profiling on some of the synthesized naphthoquinones revealed good activities against different tumor cell lines, with juglonbutin showing a remarkable activity against GSK3β with an IC50 value of 2 μM.

    12. Metathesis

      Modulation of Olefin Metathesis Reactions by Chelation

      Swetlana Scherbakow, Manfred Keller and Willi Bannwarth

      Article first published online: 15 JUL 2014 | DOI: 10.1002/ejoc.201402319

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      The hitherto unknown modulation of catalytic activity by adjacent chelating entities is demonstrated for ring-closing metathesis (RCM) as well as for cross metathesis (CM) reactions. For this purpose, a Hoveyda-type metathesis catalyst is modified by employing two different chelators. Their complexation led to an enhancement and adjustment of the catalytic activity.

    13. Fluorinated Compounds

      One-Pot Preparation of Enantiopure Fluorinated β-Amino Acid Precursors

      Joshua H. Jones, Chandrakumar Appayee and Stacey E. Brenner-Moyer

      Article first published online: 15 JUL 2014 | DOI: 10.1002/ejoc.201402369

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      An organocascade reaction enabling the transformation of enals into α-fluoro- and α,α-difluoro-β-amino aldehydes in a single flask is described. This organocascade reaction combines carbon–nitrogen and carbon–fluorine bond-forming reactions. It is thus a new approach to fluorinated β-amino acid precursors, and generates products not accessible by existing one-pot methods.

    14. Chemoselective Alkylation

      Chemoselective Synthesis of N-Protected Alkoxyprolines under Specific Solvation Conditions

      Voichita Mihali, Francesca Foschi, Michele Penso and Gianluca Pozzi

      Article first published online: 15 JUL 2014 | DOI: 10.1002/ejoc.201402429

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      Several N-protected hydroxyprolines (trans-4-Hyp, cis-4-Hyp, trans-3-Hyp) were O-alkylated with activated, nonactivated, and polyfluorinated alkyl halides by using a THF/DMSO mixture as solvent. The reaction proceeds through the formation of the oxy-carboxy dianion and is completely chemoselective owing to specific solvation of the carboxyanion function.

    15. Heterocyclic Couplings

      Triarylbismuthanes as Threefold Aryl-Transfer Reagents in Regioselective Cross-Coupling Reactions with Bromopyridines and Quinolines

      Maddali L. N. Rao and Ritesh J. Dhanorkar

      Article first published online: 15 JUL 2014 | DOI: 10.1002/ejoc.201402455

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      Cross-couplings of bromopyridines and bromoquinolines using triarylbismuth reagents have been carried out under palladium-catalysed conditions. The reactivity was high with both mono- and dibromopyridyl substrates, and mono- and bis-coupling products were formed regioselectively in good to high yields.

    16. Diastereoselective Arylation

      Boron/Zinc Exchange Reaction in the Diastereoselective Arylation of N-Protected L-Prolinal

      Bruna S. Martins and Diogo S. Lüdtke

      Article first published online: 15 JUL 2014 | DOI: 10.1002/ejoc.201402508

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      The boron/zinc exchange reaction has been used to generate aryl groups for use in a highly diastereoselective Felkin–Anh arylation of N-trityl-L-prolinal to give amino alcohols. A competing Cram-chelation pathway is prevented by the bulky trityl group at the pyrrolidine nitrogen atom. The amino alcohols possess structures that might be useful for the preparation of chiral ligands and catalysts.

    17. Carbocycles

      Stereoselective Synthesis of Enantiopure Oxetanes, a Carbohydrate Mimic, an ϵ-Lactone, and Cyclitols from Biocatalytically Derived β-Hydroxy Esters as Chiral Precursors

      Debabrata Das, Joydev Halder, Rajib Bhuniya and Samik Nanda

      Article first published online: 15 JUL 2014 | DOI: 10.1002/ejoc.201402521

      Thumbnail image of graphical abstract

      Several enantiopure α-substituted β-hydroxy esters have been synthesized using fermenting cells of K. pneumoniae. A distinctive transformation-based strategy was adopted to access several carbocyclic and heterocyclic scaffolds. The synthesized scaffolds were further diversified by the use of stereoselective dihydroxylation to access cyclitols with glycosidase inhibitory activity.

    18. Asymmetric Cross-Aldol Reactions

      Synthesis of α,β-Unsaturated δ-Lactones by Vinyl Acetate Mediated Asymmetric Cross-Aldol Reaction of Acetaldehyde: Mechanistic Insights

      Manjeet Kumar, Arvind Kumar, Masood Rizvi, Manoj Mane, Kumar Vanka, Subhash C. Taneja and Bhahwal Ali Shah

      Article first published online: 15 JUL 2014 | DOI: 10.1002/ejoc.201402551

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      A tandem asymmetric cross-aldol reaction involving the in situ generation of acetaldehyde from vinyl acetate provides access to α,β-unsaturated δ-lactones as well as isochromenones with high enantioselectivities. DFT studies were performed to gain mechanistic insights into the reaction.

  10. Short Communications

    1. Cross-Coupling

      Efficient One-Pot Cross-Coupling of Two Aryl Halides by Stannylation/Stille Reaction in Water under Microwave Irradiation

      Xin Tan, Zi Jie Zhou, Jia Xin Zhang and Xin Hong Duan

      Article first published online: 15 JUL 2014 | DOI: 10.1002/ejoc.201402404

      Thumbnail image of graphical abstract

      A one-pot cross-coupling of two aryl halides by stannylation/Stille reaction is reported. This approach includes the elimination of isolation/purification steps of the aryl stannanes, and the combined use of microwave heating and water as a single solvent makes this protocol simple, step economical, and highly efficient for the synthesis of a wide range of biaryls.

    2. Lewis Acid Catalyzed Cyclization

      Lewis Acid Catalyzed Synthesis of Cyclic Carbonates, Precursors of 1,2- and 1,3-Diols­

      Johan Cornil, Laurine Gonnard, Amandine Guérinot, Sébastien Reymond and Janine Cossy

      Article first published online: 11 JUL 2014 | DOI: 10.1002/ejoc.201402557

      Thumbnail image of graphical abstract

      FeCl3·6H2O and InCl3 are able to catalyze the cyclization of allylic and homoallylic tert-butyl carbonates into their cyclic counterparts, which are direct precursors of 1,2- and 1,3-diols. The method was used as the key step in a short synthesis of an aryl heptanoid natural product (3S,5S)-alpinikatin.

  11. Full Papers

    1. Natural Product Synthesis

      Stereoselective Total Syntheses of Paecilomycins E and F through a Protecting Group Directed Diastereoselective Intermolecular Nozaki–Hiyama–Kishi (NHK) Reaction

      Debendra K. Mohapatra, D. Sai Reddy, N. Arjunreddy Mallampudi and Jhillu S. Yadav

      Article first published online: 11 JUL 2014 | DOI: 10.1002/ejoc.201402133

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      The convergent and concise total syntheses of paecilomycins E and F were achieved through 10 linear steps in high overall yields from known intermediates. A protecting group directed diastereoselective intermolecular Nozaki–Hiyama–Kishi (NHK) reaction, a Julia–Kocienski olefination, a Sharpless asymmetric dihydroxylation, and De Brabander's lactonization protocol were employed as the key steps.

    2. Pi Interactions

      Aliphatic C–H/π and Heteroatom/π Interactions in N-Aryl-3,4-(9′,10′-dihydro­anthracene-9′,10′-diyl)succinimides

      Laura Raimondi, Maurizio Benaglia and Franco Cozzi

      Article first published online: 11 JUL 2014 | DOI: 10.1002/ejoc.201402288

      Thumbnail image of graphical abstract

      Molecular balances based on the dihydroanthracenylsuccinimide scaffold allowed C–H/π and lone-pair/π interactions of different R and R1 groups with a benzene ring to be studied.

    3. Radical Alkylation

      Synthesis of Enantiomerically Pure (α-Phen­ylalkyl)amines with Substituents at the ortho Position through Diastereo­selective Radical Alkylation Reaction of Sulfinimines

      José A. Fernández-Salas, M. Mercedes Rodríguez-Fernández, M. Carmen Maestro and José L. García-Ruano

      Article first published online: 11 JUL 2014 | DOI: 10.1002/ejoc.201402355

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      ortho-Substituted N-(tert-butylsulfinyl)benzaldimines are excellent acceptors in the intermolecular addition reactions of alkyl radicals. Easy removal of the sulfinyl group affords enantiopure α-branched amines. This short two-step sequence has been successfully applied to prepare ortho-hydroxy- and ortho-methoxybenzylamines, which are widely used as building blocks in chiral catalysis.

    4. Radical Reactions

      Fragmentation of Carbohydrate Anomeric Alkoxyl Radicals: Synthesis of Chiral ­Polyhydroxylated β-Iodo- and Alkenylorganophosphorus(V) Compounds

      Daniel Hernández-Guerra, María S. Rodríguez and Ernesto Suárez

      Article first published online: 11 JUL 2014 | DOI: 10.1002/ejoc.201402387

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      The reaction of 2,3-dideoxy-3-phosphoryl carbohydrate derivatives with (diacetoxyiodo)benzene and iodine is a direct approach to the preparation of β-iodophosphonates and β-iodophosphine oxides, which may be valuable as synthetic precursors of complex chiral molecules containing phosphorus.

    5. Total Synthesis

      A Concise Synthesis of Mupirocin H Using a Cross-Metathesis-Based Strategy

      Sandip Sengupta and Taebo Sim

      Article first published online: 11 JUL 2014 | DOI: 10.1002/ejoc.201402442

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      A highly efficient (10.1 % overall yield) and convergent (longest linear sequence of 16 steps) synthesis of mupirocin H is described, starting from commercially available (+)-(R)-Roche ester.

    6. Trifluoromethyl Thioethers

      (Trifluoromethyl)thiolation of 2-Alkynylbenzoates: An Efficient Route to 4-[(Trifluoromethyl)thio]-1H-isochromen-1-ones

      Yuewen Li, Guangming Li and Qiuping Ding

      Article first published online: 11 JUL 2014 | DOI: 10.1002/ejoc.201402629

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      We describe a trifluoromethylthiolation/cyclization protocol for the synthesis of 4-[(trifluoromethyl)thio]-1H-isochromen-1-ones through the reaction of 2-(2-alkynyl)benzoates with trifluoromethanesulfanylamide in good yields under mild conditions. A combination of the Lewis acids BiCl3 and BF3·Et2O serves as the activator for the transformation.

    7. Trifluoromethylthiolation

      Synthesis of Allylic and Propargylic Trifluoromethyl Thioethers by Copper(I)-Catalyzed Trifluoromethylthiolation of Allylic Bromides and Propargylic Chlorides

      Mingguang Rong, Dongzhe Li, Ronglu Huang, Yangjie Huang, Xiaoyan Han and Zhiqiang Weng

      Article first published online: 10 JUL 2014 | DOI: 10.1002/ejoc.201402480

      Thumbnail image of graphical abstract

      We report a copper(I)-catalyzed trifluoromethylthiolation of allylic bromides and propargylic chlorides by using elemental sulfur and CF3SiMe3 to synthesize allylic and propargylic trifluoromethyl thioethers. This method, which can tolerate a number of functional groups, afforded a variety of desired products in moderate to excellent yields.

  12. Short Communications

    1. Cross-Coupling

      Nickel-Catalyzed One-Pot Suzuki–Miyaura Cross-Coupling of Phenols and Arylboronic Acids Mediated by N,N-Ditosylaniline

      Liangshun Chen, Hongyue Lang, Lei Fang, Mengyun Zhu, Jinqian Liu, Jianjun Yu and Limin Wang

      Article first published online: 8 JUL 2014 | DOI: 10.1002/ejoc.201402475

      Thumbnail image of graphical abstract

      N,N-Ditosylaniline is extensively investigated for the first time in the one-pot Suzuki–Miyaura cross-coupling of phenols with arylboronic acids. High chemical selectivity is observed between the phenols and amines, and the desired biphenyl products containing a free amino group are obtained in good yields. dppp = 1,3-bis(diphenylphosphino)propane.

  13. Full Papers

    1. Reductive Hydroamination

      Indium-Catalyzed Hydroamination/Hydrosilylation of Terminal Alkynes and Aromatic Amines through a One-Pot, Two-Step Protocol

      Norio Sakai, Nobuaki Takahashi and Yohei Ogiwara

      Article first published online: 7 JUL 2014 | DOI: 10.1002/ejoc.201402544

      Thumbnail image of graphical abstract

      Indium tribromide effectively catalyzed both the hydroamination of alkynes with aromatic amines and the subsequent hydrosilylation of their imine intermediates to produce the corresponding secondary amines.

    2. Heteroannulation

      Base-Catalyzed Intramolecular 5-exo-dig Cyclization of 2-Propynyl-1,3-dicarbonyl Compounds: An Atom-Economic Route to Stereodefined 2-Methylene-2,3-dihydrofurans

      Quan Ma, Yeming Wang, Yuegang Zhao, Peiqiu Liao, Bo Sun and Xihe Bi

      Article first published online: 7 JUL 2014 | DOI: 10.1002/ejoc.201402542

      Thumbnail image of graphical abstract

      A regio- and stereoselective 5-exo-dig cyclization of 2-propynyl-1,3-dicarbonyl compounds under metal-free conditions has been developed. This reaction constitutes a new and straightforward method for the efficient synthesis of stereodefined 2-methylene-2,3-dihydrofurans. Spiro-dihydrofurans can also be prepared in excellent yields by this approach.

    3. Oxidation of Alkynes

      Ruthenium-Catalyzed Synthesis of 1,2-Diketones from Alkynes

      Yanan Miao, Antoine Dupé, Christian Bruneau and Cédric Fischmeister

      Article first published online: 7 JUL 2014 | DOI: 10.1002/ejoc.201402447

      Thumbnail image of graphical abstract

      The ruthenium-catalyzed synthesis of 1,2-diketones through the oxidation of alkynes by using sodium hypochlorite has been investigated. The reaction operates under an environmentally friendly procedure with regard to the oxidant and solvent. A series of diketones were prepared in good yields from electron-rich alkynes, whereas electron-poor alkynes led to lower yields.

    4. Solid-State Structures

      Controllable Supramolecular Architectures for Modulating Optical Properties on the Molecular Aggregation Level

      Runsheng Jiang, Zheng Xue, Yongjun Li, Zhihong Qin, Yuliang Li and Daoben Zhu

      Article first published online: 4 JUL 2014 | DOI: 10.1002/ejoc.201402460

      Thumbnail image of graphical abstract

      Light-controlled intramolecular charge transfer from the trithiophene unit to the perylene bisimide in the solid state can induce a hypochromatic shift and enhanced fluorescent emission.

  14. Microreviews

    1. Organocatalysis

      N-Heterocyclic Carbene Catalysis as a Tool for Gaining Access to the 3,4-Dihydropyran-2-one Skeleton

      Domenico C. M. Albanese and Nicoletta Gaggero

      Article first published online: 4 JUL 2014 | DOI: 10.1002/ejoc.201402024

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      Recent years have seen the development of methods for the synthesis of 3,4-dihydropyran-2-ones, known as medicinal agents and building blocks. Progress on N-heterocyclic carbene (NHC) chemistry has given rise to a number of reactive catalytic intermediates, in particular enols/enolates and α,β-unsaturated acylazolium ions, which provide the title compounds through different synthetic pathways.

    2. Glycopeptidomimetics

      From Glycopeptides to Glycopeptoids

      Thomas Szekely, Olivier Roy, Sophie Faure and Claude Taillefumier

      Article first published online: 4 JUL 2014 | DOI: 10.1002/ejoc.201402238

      Thumbnail image of graphical abstract

      Peptoids (N-substituted glycine oligomers) represent a family of peptide mimics in which the side chains are located on the amide nitrogen atoms rather than the α-carbon atoms. The extension of this principle to glycopeptides led to the emergence of glycopeptoids, which can be used not only as hydrolytically stable glycopeptidomimetics, but also as glycoclusters for various binding events.

  15. Short Communications

    1. Multicomponent Reactions

      Pyrrolidinone and Piperidinone Isocyanides from Isocyano Esters

      Madjid Ait Sidhoum, Aurélie Dos Santos, Laurent El Kaïm and Laetitia Legras

      Article first published online: 3 JUL 2014 | DOI: 10.1002/ejoc.201402572

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      A new family of isocyano-substituted lactams is created from isocyano esters through an alkylation/amidification process. Their use in Passerini and Ugi reactions is explored.

  16. Full Papers

    1. Total Synthesis

      Total Synthesis of (–)-Heliespirone A and (+)-Heliespirone C

      Philip Norcott and Christopher S. P. McErlean

      Article first published online: 2 JUL 2014 | DOI: 10.1002/ejoc.201402420

      Thumbnail image of graphical abstract

      Total syntheses of the epimeric natural products (–)-heliespirone A and (+)-heliespirone C are described. The successful strategy involved an aromatic Claisen rearrangement, a diastereoselective Sharpless asymmetric dihydroxylation (AD) reaction, and an intramolecular oxa-Michael addition.

    2. Alkaloid Synthetic Considerations

      5-Aminopenta-2,4-dienals: Synthesis, Activation towards Nucleophiles, Molecular Modeling and Biosynthetic Implications in Relation to the Manzamine Alkaloids

      Lok-Hang Yan, Adam Skiredj, Yves Dory, Bernard Delpech and Erwan Poupon

      Article first published online: 2 JUL 2014 | DOI: 10.1002/ejoc.201402331

      Thumbnail image of graphical abstract

      Electrophilic activation of aminopentadienals and reactions of corresponding iminium ions with various nucleophiles have been studied, accompanied by molecular modeling of these species. A foremost consideration during these studies was the importance of such reactive species in biosynthetic hypotheses concerning the formation of complex marine alkaloids related to manzamines and congeners.

  17. Microreviews

    1. Organic Solar Cells

      Organometallic Approaches to Conjugated Polymers for Plastic Solar Cells: From Laboratory Synthesis to Industrial Production

      Giuseppe Marzano, Cosimo V. Ciasca, Francesco Babudri, Gabriele Bianchi, Andrea Pellegrino, Riccardo Po and Gianluca M. Farinola

      Article first published online: 1 JUL 2014 | DOI: 10.1002/ejoc.201402226

      Thumbnail image of graphical abstract

      Current organometallic approaches to the synthesis of polymers for plastic solar cells are reviewed, with emphasis also on the requirements for industrial scale-up. The number of synthetic steps for obtaining monomers, the efficiency of the polymerization protocols, and structural simplicity are key to making organic photovoltaics a viable energy source.

  18. Full Papers

    1. Self-Assembly

      The Side Chain Makes the Difference: Investigation of the 2D Self-Assembly of 1,3,5-Tris[4-(4-pyridinyl)phenyl]benzene Derivatives by Scanning Tunneling Microscopy

      Daniel Trawny, Lucie Vandromme, Jürgen P. Rabe and Hans-Ulrich Reissig

      Article first published online: 30 JUN 2014 | DOI: 10.1002/ejoc.201402178

      Thumbnail image of graphical abstract

      A series of star-shaped compounds with different pyridine end groups is prepared, and the 2D self-assembly of these compounds is investigated by scanning tunneling microscopy (STM). Small variations in the substitution pattern lead to remarkably different self-assembly behavior. A reduction of the symmetry of the compounds has a particularly strong effect on the self-assembly result.

  19. Microreviews

    1. Task-Specific Ionic Liquids

      Point-Functionalization of Ionic Liquids: An Overview of Synthesis and Applications

      Cinzia Chiappe and Christian Silvio Pomelli

      Article first published online: 27 JUN 2014 | DOI: 10.1002/ejoc.201402093

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      The versatility of ionic liquids can be conveniently exploited by introducing specific functional groups at selected positions of the cation or anion. These salts (task-specific ionic liquids) can be synthesized through simple and straightforward procedures.

  20. Full Papers

    1. β-Oxo Sulfones

      Iron(III)-Catalyzed Aerobic Oxidation and Cleavage/Formation of a C–S Bond

      Xiaokang Shi, Xiaoyu Ren, Zhiyong Ren, Jian Li, Yuling Wang, Sizhuo Yang, Jixiang Gu, Qiang Gao and Guosheng Huang

      Article first published online: 26 JUN 2014 | DOI: 10.1002/ejoc.201402377

      Thumbnail image of graphical abstract

      An efficient method is presented for the synthesis of β-oxo sulfones from vinylarenes and dimethyl sulfoxide (DMSO) in the presence of an iron catalyst, hydrazine, and oxygen. The results show good product yields and functional group tolerance. This reaction proceeds through a C–S bond cleavage without the need of additional initiators to form a new C–S bond from DMSO.

    2. Propargylamines

      Synthesis of N,N-Disubstituted 3-Amino-1,4-diynes and 3-Amino-1-ynes by Addition of Alkynyldimethylaluminum Reagents to N,N-Disubstituted Formamides and N,O-Acetals

      Balaji L. Korbad and Sang-Hyeup Lee

      Article first published online: 25 JUN 2014 | DOI: 10.1002/ejoc.201402464

      Thumbnail image of graphical abstract

      A range of alkynyldimethylaluminum reagents were added to N,N-disubstituted formamides and the their acetals to provide the corresponding N,N-disubstituted 3-amino-1,4-diynes. Also, these reagents smoothly underwent the addition to N,O-acetals to give the corresponding N,N-disubstituted 3-amino-1-ynes.

    3. Surface Functionalization

      Diazocines on Molecular Platforms

      Tobias Tellkamp, Jun Shen, Yoshio Okamoto and Rainer Herges

      Article first published online: 24 JUN 2014 | DOI: 10.1002/ejoc.201402541

      Thumbnail image of graphical abstract

      A bridged diazocine has been synthesized whose switching direction is restricted to one side. The diazocine was mounted onto a molecular platform which is known to have a high affinity to gold Au(111) surfaces. Upon irradiation of the thermodynamically more stable cis configuration in solution with light of 385 nm the trans isomer is formed and with green light (530 nm) back-isomerization to the cis form is achieved.

    4. Tetrasubstituted Imidazoles

      Selective Synthesis of Tetrasubstituted 4-(Tetrazol-5-yl)-1H-imidazoles from 2-(Tetrazol-5-yl)-2H-azirines

      Ana Lúcia Cardoso, Américo Lemos and Teresa M. V. D. Pinho e Melo

      Article first published online: 24 JUN 2014 | DOI: 10.1002/ejoc.201402559

      Thumbnail image of graphical abstract

      The zinc trifluoromethanesulfonate [Zn(OTf)2] catalyzed reaction of 2-(tetrazol-5-yl)-2H-azirines with imines is explored. This method offers the selective synthesis of a wide range of new unsymmetrically 1,2,4,5-tetrasubstituted imidazoles, which are molecules with potential relevance in medicinal chemistry. PNB = p-nitrobenzyl.

    5. Polyphenols

      Protecting-Group-Free Solid-Phase Anchoring of Polyphenolic C-Glucosidic Ellagitannins and Synthesis of 1-Alkylamino-Vescalagin Derivatives

      Céline Douat, Emanuela Berni, Rémi Jacquet, Laurent Pouységu, Denis Deffieux and Stéphane Quideau

      Article first published online: 24 JUN 2014 | DOI: 10.1002/ejoc.201402444

      Thumbnail image of graphical abstract

      A protecting-group-free method immobilizes the protein-binding polyphenolic C-glucosidic ellagitannin vescalagin on a solid support. A functionalizing resin-cleavage method introduces amino groups at the C-1 position of the vescalagin core, and its adaptation to liquid-phase conditions offers convenient chemo- and stereoselective access to 1-alkylamino-vescalagin derivatives in good yields.

  21. Microreviews

    1. Functionalization of Imidazo[1,2-a]­pyridines by Means of Metal-Catalyzed Cross-Coupling Reactions

      Jamal Koubachi, Saïd El Kazzouli, Mosto Bousmina and Gérald Guillaumet

      Article first published online: 18 JUN 2014 | DOI: 10.1002/ejoc.201400065

      Thumbnail image of graphical abstract

      The latest developments in the field of imidazo[1,2-a]pyridine functionalization by means of cross-coupling reactions such as the Sonogashira, Heck, Negishi, Suzuki–Miyaura, and Stille reactions, as well as by C-arylation, C-alkenylation, carbonylation, and double functionalization, are reviewed and discussed.

  22. Full Papers

    1. 3-Hydroxypipecolic Acid

      A Short, Chemo-Enzymatic Synthesis of Both Enantiomers of trans-3-Hydroxy­pipecolic Acid

      Stefano Begliomini, Lorenzo Sernissi, Dina Scarpi and Ernesto G. Occhiato

      Article first published online: 16 JUN 2014 | DOI: 10.1002/ejoc.201402258

      Thumbnail image of graphical abstract

      The Suzuki–Miyaura cross-coupling reaction of a lactam-derived enol phosphate, followed by hydroboration/oxidation, is employed for the synthesis of a 2-heteroaryl-3-hydroxypiperidine whose enantiomers are separated by enzymatic kinetic resolution. Both enantiomers are then converted into the corresponding 3-hydroxypipecolic acids, thus obtained in 6 or 7 steps and 15–17 % overall yield.

  23. Microreviews

    1. Asymmetric Allylic Functionalization

      Transition-Metal-Catalyzed Allylic Substitutions of Trichloroacetimidates

      Jeffrey S. Arnold, Qi Zhang and Hien M. Nguyen

      Article first published online: 3 JUN 2014 | DOI: 10.1002/ejoc.201402097

      Thumbnail image of graphical abstract

      Allyl trichloroacetimidates are substrates of great utility for the synthesis of carbon-heteroatom bonds. Overman's pioneering work and pursuit of mechanistic understanding in rearrangements of allyl imidates has inspired the development of new allylic substitution methods for regio- and enantioselective construction of C–O, C–N, and C–F connectivity in good yields and with excellent selectivity.

  24. Full Papers

    1. Iminosugars

      Polyhydroxyamino-Piperidine-Type Iminosugars and Pipecolic Acid Analogues from a D-Mannose-Derived Aldehyde

      Camilla Matassini, Stefania Mirabella, Xhenti Ferhati, Cristina Faggi, Inmaculada Robina, Andrea Goti, Elena Moreno-Clavijo, Antonio J. Moreno-Vargas and Francesca Cardona

      Article first published online: 27 MAY 2014 | DOI: 10.1002/ejoc.201402427

      Thumbnail image of graphical abstract

      The synthesis of diversely substituted polyhydroxypiperidines, polyhydroxyaminopiperidines, and trihydroxypipecolic acid derivatives is reported, using Strecker reactions and double reductive aminations, starting from a D-mannose-derived aldehyde.

  25. Microreviews

    1. Enantioselective Protonation

      Progress in Catalytic Asymmetric Protonation

      Sylvain Oudeyer, Jean-François Brière and Vincent Levacher

      Article first published online: 22 MAY 2014 | DOI: 10.1002/ejoc.201402213

      Thumbnail image of graphical abstract

      This review provides an overview of recent advances in catalytic enantioselective protonation of preformed enol derivatives and catalytically generated enolates or equivalents through various cascade reaction sequences giving access to a large range of enantioenriched compounds containing tertiary stereocentres.

  26. Full Papers

    1. Nucleoside Analogues

      Synthesis and Biological Activity of Triazole-Appended N,O-Nucleosides

      Roberto Romeo, Salvatore V. Giofrè, Caterina Carnovale, Maria A. Chiacchio, Agata Campisi, Raffaella Mancuso, Santa Cirmi and Michele Navarra

      Article first published online: 15 MAY 2014 | DOI: 10.1002/ejoc.201402106

      Thumbnail image of graphical abstract

      1,2,3-Triazole-appended N,O-nucleosides have been synthesized by an approach combining a 1,3-dipolar cycloaddition and an alkyne–azide click chemistry reaction. The synthesized compounds showed antiproliferative activity against tumor cell lines. These nucleoside analogues could be promising scaffolds for the construction of new anticancer agents.

  27. Microreviews

    1. Palladium Catalysis

      Direct Allylic Functionalization Through Pd-Catalyzed C–H Activation

      Frédéric Liron, Julie Oble, Mélanie M. Lorion and Giovanni Poli

      Article first published online: 6 MAY 2014 | DOI: 10.1002/ejoc.201402049

      Thumbnail image of graphical abstract

      This review outlines some selected examples and present challenges relating to palladium-catalyzed direct allylic functionalization. This old reaction, ignored for many years, is enjoying a new age.

  28. Full Papers

    1. Nitrogen Heterocycles

      α-Acryloylamidoalkyl Sulfones in a Synthetic Approach for the Preparation of 6-Alkyltetrahydropyridin-2-ones

      Nicola Lucchetti, Stefano Lancianesi and Marino Petrini

      Article first published online: 23 APR 2014 | DOI: 10.1002/ejoc.201402116

      Thumbnail image of graphical abstract

      The reaction of allylzinc bromides with α-acryloylamidoalkyl sulfones provides straightforward access to the corresponding homoallylamines, which can undergo a ring-closing metathesis reaction to give 6-alkyltetrahydropyridin-2-ones. Homoallylamino derivatives that contain a branched terminal alkene moiety preferentially proceed in a cross-metathesis reaction to give N-substituted fumaramides.

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